Automatic fire extinguishing apparatus

ABSTRACT

Automatic Fire Extinguishing Apparatus which is independent of commercial utilities such as water supply, electrical service and the like, comprising a local pressurized source of extinguishing fluid and a plurality of flexible distribution hoses having sets of nozzles, said hoses also having detecting electrical conductors which respond to heat and which are connected to responsive power equipment controlling valves for releasing the extinguishing fluid under conditions of fire. The conductors and responsive power equipment include heat insulation providing a special delay action by which normal changes in ambient temperature have no effect whereas a quick rise in ambient temperature causes quick response of the extinguisher.

United States Patent [72] Inventor Elwood R. I-Iorwinski Chesire, Conn.[21] Appl. No. 851,624 [22] Filed Aug. 20, 1969 [45] Patented Sept. 7,1971 [73] Assignee Lewis Engineering Company Naugatuck, Conn.

[54] AUTOMATIC FIRE EXTINGUISHING APPARATUS 15 Claims, 7 Drawing Figs.

[52] 11.8. CI 169/5 [51 1 Int. Cl A62c 35/00 [50] FieldofSearch169/1,2,5, 16, 19,23,27,42, l B;138/111,104,33, 12 132,133,138,149

[56] References Cited UNITED STATES PATENTS 2,308,342 1/1943 Wilkinsonet a1. 138/133 2,815,818 12/1957 Douglass 169/2 FOREIGN PATENTS 489,4897/1938 Great Britain 169/23 936,302 9/1963 Great Britain 169/23 PrimaryExaminer-M. Henson Wood, .lr. Assistant Examiner-Edwin D. GrantAttorney-H. Gibner Lehmann ABSTRACT: Automatic Fire ExtinguishingApparatus which is independent of commercial utilities such as watersupply, electrical service and the like, comprising a local pressurizedsource of extinguishing fluid and a plurality of flexible distributionhoses having sets of nozzles, said hoses also having detectingelectrical conductors which respond to heat and which are connected toresponsive power equipment controlling valves for releasing theextinguishing fluid under conditions of fire. The conductors andresponsive power equipment include heat insulation providing a specialdelay action by which normal changes in ambient temperature have noeffect whereas a quick rise in ambient temperature causes quick responseof the extinguisher.

PATENTEUSEP Han 3.s03;403

SHEEI 1 OF 2 INVENTOR.

Elwood R. Hor'wins\ l AGENT PATENTED SEP 7 ISII SHEET 2 OF 2 mvemonElwood. R.Hovw(.nski J T on 0m AGENT TRIGGER AUTOMATIC FIREEXTINGUISIIING APPARATUS CROSS- REFERENCES TO RELATED APPLICATIONS l.Copending application of Elwood R. Horwinski, Ser. No. 755,203 filedAug. 26, 1968, entitled Tamperproof Cable and Detection System andhaving common ownership with the present application.

-2. Copending application of Conrad S. Ham et al., Ser. No. 780,931,filed Oct. 28, 1968, entitled Printed-Circuit Type Security Apparatusfor Protecting Areas and having common ownership with the presentapplication.

3. Copending application of Elwood R. Horwinski, Ser. No. 761,725 filedSept. 23, 1968, entitled Area Security Apparatus and having commonownership with the present application.

4. Copending application of Elwood R. Horwinski, Ser. No. 777,397 filedNov. 20, 1968, entitled Area Security System Comprising Strain and HeatResponsive Network and having common ownership with the presentapplication.

5. Copending application of Elwood R. I-Iorwinski, Ser. No. 81 1,685,filed Mar. 3, 1969, entitled Electrical Apparatus and Method forMonitoring Conditions" and having common ownership with the presentapplication.

6. Copending application of Elwood R. Horwinski, Ser. No. 790,784, filedJan. 13, 1969, entitled Safety Cable and having common ownership withthe present application.

BACKGROUND This invention relates to automatic fire extinguishingsystems. Heretofore systems of the kind indicated, which wereindependent of commercial utilities such as water, electricity etc. havebeen proposed and produced. While these systems were operative undercertain given conditions they lacked sufficient sensitivity of responseto fire while remaining dormant or inoperative for normal variations inthe ambient temperature.

SUMMARY The above drawbacks of prior fire extinguisher systems areobviated by the present invention, one object being the provi- 'sion ofan improved, wholly self-contained extinguisher which is independent ofcommercial utilities and which has an especially sensitive response tofire conditions while being relatively insensitive to normal variationsin ambient temperature. This is accomplished by a novel combinationcomprising a local pressurized source of extinguishing liquid connectedwith flexible, orificed distribution hoses through valves which areelectrically operated. The hoses have detecting conductors responding toheat and connected with power actuators for the valves, said actuatorsincluding electrical bridges. Certain conductors are provided with heatinsulation to cause unbalanced the bridge and opening of the valves forrapid rises in ambient temperature, while maintaining a bridge balanceand closed valve condition for normal, slow changes in ambienttemperature. Where the extinguishing fluid is carbon dioxide, theorifices along the distribution hoses can be normally open. Thoseorifices which are not near heat will quickly freeze closed, when theyare of small size due to evaporative cooling whereby only orifices inthe vicinity of the fire where they are heated will remain operative todischarge the C Another object of the invention is to provide animproved fire extinguisher system as above set forth, wherein automaticshut-off of the extinguishing fluid is effected in the case of smallfires which are quickly put out, and wherein a nonreversibleextinguishing action occurs in the case of large fires which are [10!quickly put out.

Other objects and advantages of the invention reside in the provision ofimproved distribution hose constructions for a system .as characterizedabove, improved sensing conductor organizations in the distributionhoses, and in the provision of an extinguishing apparatus of the kindindicated, which is especially simple and foolproof, relativelyeconomical, reliable in its operation, and adaptable to a wide varietyof situations.

Still other features and advantages will hereinafter appear.

in the drawings:

FIG. 1 is a fragmentary perspective view of an automatic, self-containedextinguishing apparatus as provided by the invention.

FIG. 2 is a fragmentary top plan view of the apparatus, showing one formof distribution hose construction. 1

FIG. 3 is a diagrammatic representation of a building structure havingincorporated in it the extinguishing apparatus.

FIG. 4 is a circuit diagram of an electrical control and indicator orsignal unit as incorporated in the apparatus.

FIG. 5 is an enlarged fragmentary side elevation of a portion of adistribution hose and sensing conductors incorporated therein. v

FIG. 6 is an end elevational view of a connector fitting and nozzleadapted to join together two hose lines or sections.

FIG. 7 is a diagrammatic showing of a solid state trigger which issubstitutable for a corresponding trigger portion of the circuit ofFlG.4. 7

Referring first to FIGS. 1-3, the improved fire extinguisher apparatusas shown thereinembraces basically a plurality of hose lines 10 (hereshown as six in number) which are connected to electrically controlledfluid valves 12 mounted on a manifold or distribution box 14 whichlatter is carried in an outer container or casing 16. The manifold 14communicates with an inner container or cylinder 18 containing carbondioxide gas under high pressure. One of the fluid distribution lines isdiagrammatically illustrated in FIG. 2, said line comprising a pluralityof hose sections 20 which are joined together by couplings or fittings22 provided with nozzles or orifices 24. An end fitting 26, also havingorifices 24, is provided on one of the hose sections 20.

In FIG. 2 only one of the hose lines 20 is illustrated, it'beingunderstood that a plurality of such lines is connected to the COcylinder 18. Although six such lines are illustrated, it will beunderstood that either a greater or a lesser number may be utilized,depending on installation requirements.

The hose lines 10 are flexible and may be of various lengths, dependingon the number of sections 20 which are utilized. In FIG. 3 there isillustrated a building structure 28 which. is equipped with the fireextinguisher system of the invention. The structure 28 is shown ashaving rooms or storage areas 30, 32 and 34 in which are disposed thelines 10 of the extinguisher, arranged in a manner considered mostefiective, depending on the material being stored or the equipment beingutilized.

In accordance with the present invention, each of the hoses 10 comprisesnot only a conduit or passage for fluid or liquid, but also electricaldetecting or sensing conductors which respond selectively to a rapidrise of ambient temperature by operating the associated electricallycontrolled valve, thereby to effect a discharge of the extinguishingfluid through the hose line. The sets of sensing conductors arerespectively con.- nected preferably with a plurality of bridge circuits(one for each hose line) which in turn control the electric valves, 1 2carried by the manifold 14.

Considering FIG. 4 there is diagrammatically illustrateda hose 10comprising a flexible conduit 36 which is preferably of spiral woundmetal. Surrounding and wound about the conduit 36 are nickel, sensingconductors 3,8, 40 and lead or equivalent low-melting point sensingconductors 42, 44. The sensing conductors 38, 40, 42 and 44 are shown asconnected respectively in the four legs of l a bridge circuit in such amanner that melting of the lead conductors will unbalance the bridge, orthat unequal changes in the resistance of the nickel conductors willlikewise unbalance the bridge. Such unequal changes of resistance canoccur in response to a rapid rise ambient temperature as from aconflagration whereas the relative resistence values will not change forgradual changes of temperature such as normally occur due to weather andlike conditions.

In effecting this, one of the nickel conductors (that indicated at isprovided with a heat-insulating jacket 46 whereby it will not respondquickly to sudden large changes in temperature as from a fire whereas itwill gradually change in temperature in keeping with changing weather orheating conditions or the like.

The bridge circuit is designated generally by the numeral 48, saidcircuit comprising a ground 50 connected by a wire 52 to the negativeterminal of a battery 54. The positive terminal of the battery 54 isconnected through a switch 56 to a wire 58 comprising one corner of thebridge. THe opposite comer" of the bridge 48 comprises a wire 60 whichis connected with the ground 50. The nickel and lead sensing conductorsare connected with corner junctures 62, and 66. The junctions 64 and 68are connected with a galvanometer type instrument 70 which controls amovable shutter 72 having an aperture 74 in it. Adjacent the movableshutter 72 is an incandescent electric lamp 76 connected by wires 78, 80and a resistor 82 to the battery 54. Closing of the switch 56 will accordingly effect illumination ofthe lamp 76.

The bridge legs have adjustable resistors 84, 86, 88 and 90 connectedrespectively with the conductors 42, 38, 40 and 44 whereby each bridgeleg constitutes a complete circuit, including certain of the sensingconductors. The battery ground 50 is connected by a wire 60 to thebridge juncture 66, and the bridge juncture 62 is connected by the wire58 to the switch 56. Accordingly, the bridge is energized from thebattery 54 and may be placed in balance by suitable adjustment of theadjustable resistors.

In conjunction with the galvanometer 70, lamp 76 and movable shutter 72there is provided a phototransistor or light sensitive cell 91 of thetransistor type, having a base 92, a collector 94 and an emitter 96. Thebase 92 is connected through a resistor 98 and wire 100 with thepositive supply wires 80 and 58 from the battery 56. The emitter 96 isconnected by a wire 102 to the bridge juncture 62 which is in turnconnected with the positive supply wire of the battery 56, and alsoconnected by a wire 104 to a relay coil 106 which is in turn connectedto an emitter 108 of a power transistor 110 whose base 112 is connectedby wire 114 to the collector of the light sensitive cell 91. A resistor116 connects the base 1 12 of the power transistor to the wire 104, saidbase being also connected througha resistor 118 and wire 120 to thecollector 122 of the transistor 110. The wire 120 to the to the bridgejuncture 66 which goes to the negative supply wire from the battery 56.

' The relay coil 106 controls moveable contacts 124, 126, the latterbeing a holding contact engageable with a stationary contact 128connected to the transistor emitter 108. The movable contact 126 isconnected through a switch 130 to the collector 122.

The movable relay contact 124 connects through a wire 132 with a battery134 which is connected to a switch 136 for controlling a signal or bell138. The bell 138 is connected by a wire 140 to the stationary contact142 which is cooperable with the relay contact 124.

In addition to the signal 138, a valve circuit control is effected byconnecting to the wires 132 and 140 a valve coil 144 and battery 146.

Operation of the circuit of FIG. 4 is as follows: With the bridgebalanced, the shutter 72 will be centralized and light from the lamp 76will strike the light sensitive cell 91. This effects a conductive pathbetween the collector and emitter 94, 96 of the cell 91, therebyeffecting a clamping action between the base 112 and emitter 108 of thetransistor 110. In other words, the effect of light striking the cell 91is such that no appreciable voltage or potential difference existsbetween the base 112 and emitter 108 of the power transistor 110.However, when the shutter 72 deflects to one side or the other duetounbalance of the bridge resulting from shorting, breaking, melting orresistance changes of any sensing wire or wires 38,

terminating the conductive path between the collector and emitter 94,96. The clamping action thus ceases, and voltage can now exist acrossthe resister 116, meaning that a potential will exist between the base112 and the collector 108 of the power transistor 110. Such voltage willrender the transistor 110 conducting whereby the relay coil 106 will beenergized by current flowing through the collector and emitter.

The result of this is that the relay coil 106, being energized, willactuate the relay contacts 124, 126. If the relay contact 126 is in thenature of a holding contact, it will maintain the relay energizedregardless of shutting off of the transistor 1 10. The relay contacts124, 126 will effect energization ofthe hell 138 and actuation of theelectric valves 144, sounding an alarm and indicating that the bridgehas been unbalanced, as by alteration of the continuity or resistance ofthe wires 38, 40, 42 or 44. Thus, according to the invention, the hose10 can respond to excessive heat by a melting of wires or changing ofresistance, which wires as later explained are especially arranged tomonitor these conditions.

Opening of the electric valve 144 will cause the CO from the container18 to flow through the designated hose 10 and out of the nozzlesthereof. Those nozzles which are not close to the heat will quicklyfreeze over and close automatically due to the small size and due to theevaporative cooling. The nozzles which are near the heat will not freezeover because they are warmed. Instead they will discharge the CO for thepurpose of extinguishing the fire.

In the event that the holding contacts 126, 128 of the relay coil 106are not utilized but instead are rendered inoperative, an automaticshutting off of the electric valve 144 can occur whenever a balance isrestored in the bridge. This can happen if none of the lead conductorshas melted, and if the tire is quickly extinguished whereby thetemperature of the noninsulated nickel sensing conductor 38 drops tonormal. However, if the fire is of considerable magnitude, sufficient tomelt the lead conductors 32, 44, then there can be no reversible actionof the bridge to restore the balance. In such case the absence of theholding contacts 126, 128 will be of no significance since the bridgewill remain permanently unbalanced, thus having the same effect as iftherelay had holding contacts and remained closed once it was actuated bythe bridge unbalance.

While FIG. 4 illustrates one specific type of bridge circuit and valvecontrol, it will be understood that the invention is not limited to sucharrangement, since others are possible without departing from the spiritof the invention.

A bridge circuit similar to that of FIG. 4, is illustrated and describedin the copending application of Elwood R. Horwinski, Ser. No. 755,203filed Aug. 26, I968 and entitled Tamperproof Cable and Detection System.

It will be understood that the electrically operated valve 144 of FIG. 4may comprise either of the valves 12 shown in FIGS. 1 and 2, and thatfor each electrically operated valve and hose line there will he acorresponding bridge circuit with sensing conductors as illustrated inFIG. 4.

In place of the trigger device comprising the galvanometer 70, mirror72, lamp 74 and phototransistor 91, a fully solidstate trigger may beemployed. In FIG. 7 such a solid state trigger is illustrated, havingterminals A, B, C, D E and F for connection to the correspondinglylettered terminals in FIG. 4. With such substitution the devices 70, 72,76, 82 and 91 will be removed from the circuit.

An advantageous hose line construction as provided by the invention isillustrated in FIGS. 4, 5 and 6. The hose line 20 shown in FIG. 5comprises the spiral metal conduit 36 which may be of well-knownconstruction, said conduit having wrapped around it the nickel sensingconductor 40 with its heat insulating jacket 46. The conductor 40 may bedisposed in the helical groove of the metal conduit 36, as shown.Wrapped over the conduit 36 and conductor 40 is a spiralwrap ribbon 148of insulating plastic. Around the wrap 148 is a second spiral wrap 150of plastic ribbon, having adhered to it meltable foil stripsconstituting the lead conductors 42, 44 AP urn A A Inn-1003'"- 8.;I'nlriklunn 1:1 In

placed around the ribbon 150 and foil strips 42, 44, thereby to coverthe strips with an insulating layer. Around the spiral wrap 152 there isa wire braid wrap 154 which contains the nickel sensing conductor 38,said conductor having enamel or equivalent insulation whereby it doesnot make electrical contact with the remaining wires of the braid.Surrounding the braid 154 is an outer insulating jacket 156 of extrudedplastic.

The conductors 40, 42, 44 and 38 may be brought out to a prongedelectrical fitting 158 at one end of a section of the hose line, suchend being provided with a threaded end fitting 160. A companion sectionof hose line 20 illustrated in FIG. 5 may also have an end fitting 160of a similar type, as well as a socket-type electrical fitting 162 whichis cooperable with the fitting 158 for the purpose of providingcontinuity of the circuits of the sensing wires.

The hose sections 20 may be joined by a fitting or coupling 164 havingturnable, internally threaded collars 166 adapted to thread onto theshort nipple portions 168 of the end fittings 160. The hose coupling 164can have one or more nozzles 170, two such nozzles being illustrated asin FIG. 6.

The above organization has a number of advantages. Hose lines of anypractical length may be readily assembled by the use of longer orshorter sections which are coupled together by the fittings 164.Discharge nozzles may be located at strategic points by selectingsuitable lengths of said hose sections; or a number of nozzle fittingsmay be joined to each other by use of suitable short nipples whereby anyjuncture between two hose sections 20 may have four, six or morenozzles, directed in different directions.

The use of the heat insulation 46 on the nickel sensing conductor 40 andthe location of said conductor closely adjacent the metal conduit 36 andremoved inwardly from the outer layers of the hose assemblage results inan advantageous delay in temperature changes of this wire. Accordingly,the nickel wire 38 will respond more rapidly than the wire 40 to suddenchanges in ambient temperature, such as may be occasioned by aconflagration, thereby resulting in an unbalance of the bridge circuitand actuation of the associated electric valve. However, when gradualchanges in ambient temperature occur, the nickel conductors 38 and 40will substantially simultaneously change their temperature andresistance whereby the balance of the associated bridge circuit will notbe disturbed. Accordingly, the system will respond rapidly to fireconditions, but will not react at all to normal changes in ambienttemperatures such as those occasioned by weather, heating conditionsinthe building, and the like.

It will now be seen from the foregoing that I have provided a novel andimproved automatic fire extinguishing system which is extremelysensitive to rapid, appreciable changes in temperature. Relativelyslight changes in the resistance of the nickel wire 38 with respect tothe resistance to the wire 40 can cause an unbalance of the bridge,whereby a sensitive response is had to fire conditions. However, inspite of such sensitive response, the apparatus will not be set off dueto normal changes of ambient temperature, as already explained above.For small conflagrations involving unbalance of the bridge only byvirtue of response of the nickel conductors, an automatic shut-off ofthe extinguishing fluid can occur when the fire has been extinguishedand the bridge restored to balance by virtue of the nickel conductorsbeing restored to their normal resistance values (provided that noholding contacts are employed in the system, such as the contacts 126,128).

Referring again to FIG. 1, the container 16 may house the bell or signalalarm 138 and may also have a signal light 172 energized simultaneouslywith the bell 138. The bridge circuits associated with the hoses 10 maybe housed in the container 16, in a suitable casing such as indicated at174, and the various batteries and a charging unit are indicated ashoused in a separate container 176. It will be understood that theapparatus as above set forth is independent of commercial utilities suchas water supply, commercial electric power and the like. The apparatusis relatively simple, and is reliable and foolproof in its operation.

Variations and modifications are possible without departing from thespirit of the invention.

I claim:

l. A combined fire detector and extinguisher hose comprising, incombination:

a. a hose line adapted to carry an extinguishing fluid,

b. a wire wrap surrounding said hose line,

c. said wrap comprising a plurality of electrical conductors insulatedfrom each other,

d. one of said conductors having a high and significant temperaturecoefficient of resistance greater than copper, thereby adapting it foruse as a temperature-responsive sensor.

2. A combined fire detector and extinguisher hose comprising, incombination:

a. a hose line adapted to carry an extinguishing fluid,

b. a wire wrap surrounding said hose line,

c. said wrap comprising a plurality of electrical conductors insulatedfrom each other,

(1. one of said conductors having a high and significant temperaturecoefficient of resistance greater than copper,

thereby adapting it for use as a temperature-responsive sensor,

a plurality of nozzles connected in said hose line to receiveextinguishing fluid therefrom and to discharge the same to thesurrounding area,

f. said nozzles having orifices sufficiently small to enable adischarging liquid to become frozen in it at temperatures caused byevaporation in a range considerably below ambient. I r

3. A hose as in claim 2, and further including: 7

a separable hose connector fitting carrying one of said nozzles anddetachably connecting the same to separate lengths of said hose line,and

b. separable electrical connector fittings for detachably connecting theconductors of said lengths at a location adjacent said one hoseconnector fitting.

4. A combined fire detector and extinguisher hose comprising, incombination:

a. a hose line adapted to carry an extinguishing fluid,

b. a wire wrap surrounding said hose line,

0. said wrap comprising a plurality of electrical conductors insulatedfrom each other,

d. one of said conductors having a high and significant temperaturecoefficient of resistance greater than copper thereby adapting it foruse as a temperature-responsive sensor,

e. two of the conductors of high temperature coefficient of resistancehave different responses to changes in ambient temperature, one of saidtwo conductors having heat insulation surrounding it to render itrelatively poorly responsive to surrounding heat and the other of saidtwo conductors being relatively readily responsive to surrounding heat.

. A hose as in claim 4, wherein:

. said other conductor of high temperature coefficient of resistancesurrounds the said one conductor in spaced relation thereto.

6. A hose as in claim 5, wherein:

a. the hose line comprises a spiral-wound flexible metal conduit havinga helical external groove,

b. said one conductor of high temperature coefficient of resistancehaving an insulating jacket and being wound in said external groove,

c. a spiral wrap of insulation surrounding said metal conduit and oneconductor,

d. said other conductor of high temperature coefficient of resistancebeing wound around and external to said spiral wrap.

7. A combined fire detector and extinguisher hose comprising incombination:

a. a hose line adapted to carry an extinguishing fluid,

b. a wire wrap surroundin said hose line.

c. said wrap comprising a plurality of electrical conductors insulatedfrom each other,

d. one of said conductors having a high and significant temperaturecoefficient of resistance greater than copper, thereby adapting it foruse as a temperature-responsive sensor,

. the conductors of high temperature coefficient comprise nickel,

othcr conductors of said sheath being constituted of lowmclting pointmetal.

A hose as in claim 7, wherein:

. two of the conductors of high temperature coefficient of resistancehave different responses to changes in ambient temperature,

b. one of said two conductors having heat insulation surrounding it torender it relatively poorly responsive to surrounding heat and c. theother of said two conductors being relatively readily responsive tosurrounding heat,

d. said other conductor of high temperature coefficient of resistancesurrounds the said one conductor in spaced relation thereto,

e. said low melting point conductors being disposed between said twoconductors of high temperature coefficient of resistance.

9. A hose as in claim 8, wherein:

a. the hose line comprises a spiral-wound flexible metal conduit havinga helical external groove,

b. said one conductor of high temperature coefficient of resistancehaving an insulating jacket and being wound in said external groove,

c. a spiral wrap of insulation surrounding said metal conduit and oneconductor,

d. said other conductor of high temperature coefficient of resistancebeing wound around and external to said spiral wrap,

e. said conductors of low melting point being carried by said spiralwrap of insulation.

10. A hose as in claim 2, and further including:

a. a supply of fire-extinguishing fluid connected to one end of saidhose line,

b. a valve controlling the flow of fluid from said supply to the hoseline,

c. an electric actuator for said valve, and

(1. means for delaying the temperature change of one of said two hightemperature coefficient conductors when changes in ambient temperatureoccur, and

e. means connected to said high-temperature coefficient conductors,responding to a rapid change in the resistance of only one of saidconductors due to a rapid change in ambient temperature surrounding saidconductors, for activating said actuator to open the valve wherebyextinguishing fluid'will be discharged through said hose line.

11. Apparatus as in claim 10, wherein:

a. the means responsive to rapid change in the resistance of one of thehigh-temperature coefficient conductors comprises a bridge circuitconnected to said valve actuator and having said conductors in its legs.

12. Apparatus as in claim 10, wherein:

a. the means for delaying the temperature change comprises heatinsulation surrounding said one high-temperature coefficient conductor.

13. Apparatus as in claim 12, wherein:

a. said other conductor is wrapped around the hose line in spacedrelation thereto,

b. said one conductor being disposed between the hose line and saidother conductor, in the space therebetween.

14. Apparatus as in claim 10, wherein:

a. the hose line comprises a spiral-wound flexible metal conduit havinga helical external metal groove,

b. said one conductor having a heat-insulating jacket and being wound insaid external groove.

15. Apparatus as in claim 11, and further including: a. a conductor oflow-melting point metal, wrapped around said hose line and connected ina leg of said bridge to in fluence the latter when the low-melting pointmetal melts and renders the conductor discontinuous.

1. A combined fire detector and extinguisher hose comprising, incombination: a. a hose line adapted to carry an extinguishing fluid, b.a wire wrap surrounding said hose line, c. said wrap comprising aplurality of electrical conductors insulated from each other, d. one ofsaid conductors having a high and significant temperature coefficient ofresistance greater than copper, thereby adapting it for use as atemperature-responsive sensor.
 2. A combined fire detector andextinguisher hose comprising, in combination: a. a hose line adapted tocarry an extinguishing fluid, b. a wire wrap surrounding said hose line,c. said wrap comprising a plurality of electrical conductors insulatedfrom each other, d. one of said conductors having a high and significanttemperature coefficient of resistance greater than copper, therebyadapting it for use as a temperature-responsive sensor, e. a pluralityof nozzles connected in said hose line to receive extinguishing fluidtherefrom and to discharge the same to the surrounding area, f. saidnozzles having orifices sufficiently small to enable a dischargingliquid to become frozen in it at temperatures caused by evaporation in arange considerably below ambient.
 3. A hose as in claim 2, and furtherincluding: a. a separable hose connector fitting carrying one of saidnozzles and detachably connecting the same to separate lengths of saidhose line, and b. separable eleCtrical connector fittings for detachablyconnecting the conductors of said lengths at a location adjacent saidone hose connector fitting.
 4. A combined fire detector and extinguisherhose comprising, in combination: a. a hose line adapted to carry anextinguishing fluid, b. a wire wrap surrounding said hose line, c. saidwrap comprising a plurality of electrical conductors insulated from eachother, d. one of said conductors having a high and significanttemperature coefficient of resistance greater than copper therebyadapting it for use as a temperature-responsive sensor, e. two of theconductors of high temperature coefficient of resistance have differentresponses to changes in ambient temperature, f. one of said twoconductors having heat insulation surrounding it to render it relativelypoorly responsive to surrounding heat and g. the other of said twoconductors being relatively readily responsive to surrounding heat.
 5. Ahose as in claim 4, wherein: a. said other conductor of high temperaturecoefficient of resistance surrounds the said one conductor in spacedrelation thereto.
 6. A hose as in claim 5, wherein: a. the hose linecomprises a spiral-wound flexible metal conduit having a helicalexternal groove, b. said one conductor of high temperature coefficientof resistance having an insulating jacket and being wound in saidexternal groove, c. a spiral wrap of insulation surrounding said metalconduit and one conductor, d. said other conductor of high temperaturecoefficient of resistance being wound around and external to said spiralwrap.
 7. A combined fire detector and extinguisher hose comprising incombination: a. a hose line adapted to carry an extinguishing fluid, b.a wire wrap surrounding said hose line, c. said wrap comprising aplurality of electrical conductors insulated from each other, d. one ofsaid conductors having a high and significant temperature coefficient ofresistance greater than copper, thereby adapting it for use as atemperature-responsive sensor, e. the conductors of high temperaturecoefficient comprise nickel, f. other conductors of said sheath beingconstituted of low-melting point metal.
 8. A hose as in claim 7,wherein: a. two of the conductors of high temperature coefficient ofresistance have different responses to changes in ambient temperature,b. one of said two conductors having heat insulation surrounding it torender it relatively poorly responsive to surrounding heat and c. theother of said two conductors being relatively readily responsive tosurrounding heat, d. said other conductor of high temperaturecoefficient of resistance surrounds the said one conductor in spacedrelation thereto, e. said low melting point conductors being disposedbetween said two conductors of high temperature coefficient ofresistance.
 9. A hose as in claim 8, wherein: a. the hose line comprisesa spiral-wound flexible metal conduit having a helical external groove,b. said one conductor of high temperature coefficient of resistancehaving an insulating jacket and being wound in said external groove, c.a spiral wrap of insulation surrounding said metal conduit and oneconductor, d. said other conductor of high temperature coefficient ofresistance being wound around and external to said spiral wrap, e. saidconductors of low melting point being carried by said spiral wrap ofinsulation.
 10. A hose as in claim 2, and further including: a. a supplyof fire-extinguishing fluid connected to one end of said hose line, b. avalve controlling the flow of fluid from said supply to the hose line,c. an electric actuator for said valve, and d. means for delaying thetemperature change of one of said two high temperature coefficientconductors when changes in ambient temperature occur, and e. meansconnected to said high-temperature coefficient conductors, responding toa raPid change in the resistance of only one of said conductors due to arapid change in ambient temperature surrounding said conductors, foractivating said actuator to open the valve whereby extinguishing fluidwill be discharged through said hose line.
 11. Apparatus as in claim 10,wherein: a. the means responsive to rapid change in the resistance ofone of the high-temperature coefficient conductors comprises a bridgecircuit connected to said valve actuator and having said conductors inits legs.
 12. Apparatus as in claim 10, wherein: a. the means fordelaying the temperature change comprises heat insulation surroundingsaid one high-temperature coefficient conductor.
 13. Apparatus as inclaim 12, wherein: a. said other conductor is wrapped around the hoseline in spaced relation thereto, b. said one conductor being disposedbetween the hose line and said other conductor, in the spacetherebetween.
 14. Apparatus as in claim 10, wherein: a. the hose linecomprises a spiral-wound flexible metal conduit having a helicalexternal metal groove, b. said one conductor having a heat-insulatingjacket and being wound in said external groove.
 15. Apparatus as inclaim 11, and further including: a. a conductor of low-melting pointmetal, wrapped around said hose line and connected in a leg of saidbridge to influence the latter when the low-melting point metal meltsand renders the conductor discontinuous.